𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Freezing-Induced Strains and Pressures in Wet Porous Materials and Especially in Concrete Mortars

✍ Scribed by Vesa Penttala


Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
742 KB
Volume
7
Category
Article
ISSN
1065-7355

No coin nor oath required. For personal study only.

✦ Synopsis


A theory based on thermodynamics will be presented by which the pressure in the pore structure of wet porous materials can be deduced during freezing. The pore structure is partly filled with liquid and inert gases such as air. The theory is based solely on thermodynamic relationships; no knowledge of the real geometry of the pore system or the degree of liquid filling in the void space is needed. The only inputs needed in the theory are relative humidity and temperature measured in the sample chamber during the freezing. The validity of the theory will be compared with the test results of mortar samples frozen and thawed in a low temperature calorimeter. During the cooling from 20 to Ϫ70°C and subsequent heating of the sample, the strains, heat capacity, and ice evolution of the samples were measured simultaneously in the calorimeter. Two of the three mortar samples were produced using an air-entraining admixture.